Stencil printing apparatus



Oct. 16, 1934. H. P. ELLIOTT 1,976,928

STENCIL PRINTING APPRATUS F11ed July 15, 1931 INVENTOR Patented Oct. 16, 1934 UNITED STATES 1,976,928 s'rENciL PRINTING APPARATUS Harmon P. Elliott, Watertown, Mass., assignor to `Elliott Addressing Machine Company, a corporation of Massachuse tts ` Application July 15, 1931, serial No. 550,335

13 Claims.

This invention relates generally to addressing apparatus of the type shown and described inmy copending application Serial No. 473,322 llled August 6, 1930, since issued as Patent No. 1,909,-

5 910 under date of May 16, 1933. The present disclosure is substantially the same as part of what was described in said copending application with the exception of one added feature, and consequently the present application constitutes a continuation in part of said application. A

More specically the present invention comprises an improved form of stencil having a re1- atively large printing area or eld, usually that 15 of the message bearing surface of a standard postal card, together with improved mechanism for handling such large stenciland a plurality of postal or post cards or letter heads or other sheets, upon each of which the stencilled legend is to be successively printed.

Heretoore it has long been customary to use a plurality of small stencil cards, each having a name and address cut therein, for addressing postalv cards, envelopes, etc., by running said stencil cards successively along guides to a printing zone in a suitable addressing machine, and to arrest such of said stencils as may be selected for two or three repeat printing of the name and address cut therein, but, so far 'as I am aware, no stencil having a large enough printing eld to include the entire message bearing face of a postal card and capable of use in an addressing machine, has been developed (prior to the reduction to practice of the invention of my above noted copending application), thus obtaining the result that the same apparatus may be used alternatively either for printing the series of addresses one upon each postal card, or for printing the same message, or other uniform matter, upon the other face.

The reasons why this result was not heretofore attained commercially were that for successful use in conjunction with such apparatus the stencil cards have heretofore had to have relatively stiff frames, which, when made large enough to present a message-printing eld will not easily assume the long arc of curvature necessarily assumed when such stencils are being cut on the platen roller of an ordinary typewriter; while,

on the other hand, if made with ilexible frames for that purpose, they then will not have enough stiness to retain their shape when being pushed back and forth rapidly an indefinite number of times through the printing zone of the addressing machine, or other in k applying apparatus of (CL lol-116) that character, to produce some hundreds or thousands of reprintings of the same lengthy legend or message.

These conflicting difficulties are both avoided by my present invention in carrying out which the following procedure is adopted: I make a highly exible stencil, any desired size, having a relatively thin paper frame. Said frame gives the stencil just the stiffness sucient to enable it to be handled in the typewriting machine, but not sufllcient to prevent it curling smoothly about the platen roll thereof during the stencil cutting operation. Then I insert such exible, cut stencil in a thin, butrelatively stiff metal carrier having a window large enough to expose the whole printing iield of such stencil, which carrier and enclosed stencil can be inserted in the guides of the .ink-applying portion of a standardwstencil printing apparatus and there withstand the pulling and thrusting of the rapidly reciprocating feeding mechanism by which it is moved back and forth through the printing zone.

A subsidiary difticulty sometimes encountered when a device of the above character is employed is a lack of certainty of initially accurate registry of the stencil with the carrier and with the ink-applying platens (usually rotating sectors) of the printing apparatus, and a failure to maintain such registry during the many successive printing operationsy to which the stencil is subjected. This difliculty is also overcome according to my present invention by employing some simple method of interlocking the stencil and the carrier, as by notching one and providing the other with a projection adapted to engage such notch.

'I'he invention has certain other objects and advantages hereinafter te be pointed out, or

which may be easily discernible by those skilled inthe art.

The best form of apparatus at present known to me, embodying my invention, is illustrated in the accompanying sheet of drawing, in which;

Fig.y 1 is a fragmentary plan view of a portion of stencil printing apparatus such as is fully shown and described in my said copending application Serial No. 473,322 with my improved flexible ,stencil and stencil carrier installed therein.

Fig. 2 is a general, vertical, longitudinal section of the structure shown in Fig. 1, with certain parts omitted. i

Fig. 3 is a detail cross-section on an enlarged scale taken on line 3-3 of Fig. 1, and

ters indicate like parts. 3 and 5 are the usual.

rotary platen sectors mounted on shafts 2 andv 55, the upper one 3 being supplied witha film of ink by any convenient inkingapparatus (not shown). These sectors are used in printing the message on one side Vof each post card; This is done with the cooperation of a stencil 7 mounted in a rectangular carrier frame indicated generally at 8. This carrier 8 is slid by hand part way into the usual groovedv guides 99 and 9, along which the usual form of` stencil cards slide to the printing zone, (in which the revolving platen sectors are located) when the addresses (instead of the message) are being printed on the other sides of the stencil cards. 94 and 95 are slide bars extending transvesely of the guide strips 9 and 99 and mounted in a fixed housing, part of which is shown at 18 in Fig. 3. Casting 101 is fastened on slide bar 95 and has stencil guide 9 fastened to its under surface. lsimilarly, casting 98 is vfastened to slide bar 94 and has stencil guide 99 fastened to its under surface. 'Ihese stencil guide strips 9 and 99 can, therefore, be slid toward or from one another to carry a stencil or stencilsof widths different from that here shown in the drawing, all as' described more in detail in my Patent No. 1,909,910, above referred to.

The stencil carrier 8 is normally retracted by tension spring 10, anchored at 11, and having its free end connected to the slide 12 which can be reciprocated on guide rod13 which is screwed into the forward one of the card magazine corner of stencil carrier frame 8. Normally such4 spring 10 holds the slide 12 back against, or near, the rubber bumper 17 mounted on guide rod 13, and, in turn, lug 14 on said slide then holds stencil carrier 8 back in retracted posi-'- tion with its rear bumper 16 resting against a horizontally extending cross bracket 18 supported on the main frame. Said carrier 8, however, is of such-length that, even when in this retracted position, its. front end extends within and slightly beyond the bite of the platen sectors 3, and 5, when the latter are revolved. 'Ihe upper sector 3 has end portions 19, 19, which are separated by narrow grooves 25 from the inking surface 20, and are outside of the ends of the inking roll so they receive no ink. They bear on the inner portions of the Asides of stencil carrier 8. When the sectors are revolved through a small angle from their position of.

rest they grasp the forward portions of the sides of stencil carrier 8 between them and thereafter pull it, together with the stencil carried ing lug 14 on slide 12, so that after the removal of the frame 8 the space between the guides will be left free and there will consequently be no interference with the adjustment of the guides for the use of the addressing stencils nor withy the passage of a succession of address bearingl stencils therethrough when address printing is being done.

At the Sametime a postcard 2l, which has previously been fed forward through guides 22 by feed drum 23 from the bottom of the stack in a magazineY represented generally by 24, has reached a position under stencil 7 such that its forward end has also been grasped by the revolving sectors, together with the stencil bearing carrier 8. Further rotation of the platen sectors then pulls the stencil 7, superposed on postcard 21, between them and forces ink through the stencil onto the upper surface of the postcard, thereby printing on the postcard the-stencilled message or other matter. Drum 23 has a' roughened rubber surface strip 35 to give frictional contact with the postcard during the proper portion of each revolutionv of said drum.

When anyone revolution of the platen sectors is completed the portions of the cutaway sections 26, 26, thereof have come opposite one another, with the result that` the stencil carrier 8 is then released from their grip, and spring l0 thereupon snaps it, and the messagestencil 7 carried thereby, back into retracted position, ready fork another cycle of operations on the next postcard when one is fed out of the magazine 24.

The blanks from which stencils 7 are made may have a flap 140 attached thereto as shown in Fig. 4. This is folded under when the blank is being stencilized on a typewriter. After stencilizing this flap is torn off, or before the stencil is inserted in carrier 8 for use.

I'he body of this blank is preferably made of a thin, loose flbred paper which has been coated with a film of a material which will be displaced by blows of the type when being written on` in a typewriting machine to form a stencil in the well known way. As indicated by the broken lines in Fig. 1 showing the inner side margins of the lower frame plate 8a and still more clearly shown in Fig. 5, the side portions of said frame are narrower than are the corresponding side portions of the upper frame 8b, which latter practically coincide with the inner margins of the edge reinforcing strips of the stencil paper frame 7.1:. This leaves the inner edges of the side portions of said paper frame 7a: unconfined` by the lower metal frame 8a so that when the still thinner panel 7, in which the stencil proper is formed, is pressed downward by the ink bearing portion 20 of the upper sector, there is no shearing action of the ends of said sector portion against the inner edges of the lower metal frame 8a, such as would occur if the said edges thereof were extended up toy lines adjacent the lines of travel ofthe grooves 25, in said sector face. On the contrary, strips of the stencil paper frame of considerable Width are thus left free to flex downward so that there is not even a sharp bending along these edges of the stencil paper during the printing operation, and still less any shearing action thereon.

In Fig. 2 a portion of the front wall of a magazine, generally represented by 24, is shown at 123. From this is supported by spring 130 a housing, 131, in which is journalled a pressure roller l132. As drum 23 is revolved in the direction ofthe arrow on its shaft 54 (by any suitable mechanism not shown) the roughened rubber strip 35, covering a portion of the drum periphery, forces the lower postcard in stack 2l under pressure roller 132 and said card, being firmly grasped between said drumand roller, is positively fed to the left along guides 22 to a position such that its forward end lies under the forward portion of carrier 8 and its contained stencil '7, said card, carrier and stencil being then within the bite of sectors 3 and 5, at the beginning of each revolution thereof, as previously described.

It will thus be seen that the grooved guides 9 and 99, the two-part stencil carrier 8a, 8b, and the notched stencil frame 7:: cooperate to ensure, at all times during the printing operation, a perfect registry between the carrier and the stencil, and between the stencil and the inkcarrying portion 20 of platen sector 3.' The clips 8c on base-portion 8a of the carrier 8 engage the notches 27 in the ends of stencil frame 7.1: and hold it in predetermined position with reference to said base portion 8a. The two superposed carrier members 8a and 8b, being of the same outside width. are held in proper registry one with the other by the grooved guides 9 and 99, into which they fit snugly, and the entire assembly so formed can be fed forward in such relation to sector 3 that the inkbearing portion 20 of the latter's face will press on the printing eld of the stencil, but on no other part thereof; while the end portions 19, 19 of the sector will bear only on the side portions of the stencil carrier and thereby exert the necessary feeding action thereon, the contained stencil being thereby relieved from all strain resulting from the feeding operation. Both portions 19 and 20 of the curved face `of the sector 3, are made of yielding material as described in my said Patent No. 1,909,910, to permit them to be slightly deformed by pressure, and to deflect the stencil sheet downward into contact with the lower platen 5, during the printing operation, consequently the end portions 19, 19, of the arc-shaped face of sector 3, which bear on the side portions of the metal stencil carrier 8, will be slightly attened down upon the same as shown in Fig. 2, while the main portion 20 of said sector face will extend downward between said carrier side portions (as shown in the dotted line in Fig. 2) and press the thin stencilized panel 7 upon the postcard 21, which latter is supported by platen sector 5 in the plane of the under surface of the grooved guides 9 and 99, thus slightly deflecting said stencil sheet downward below its normal,- which is approximately the medial plane of the grooves in said guide bars 9 and 99. This action can be readily understood by looking at Fig. 5, though the scale of Fig. 2 is too small to clearly distinguish the two elements (post card and stencil sheet) compressed together between sectors 3 and 5.

Various changes could be made in the details of the construction above described, without departing from the underlying principles of the invention, so long as the relative arrangement of, and cooperation between, the parts, or some of them, are retained within the limits defined by the appended claims.

Having described my invention, I claim,

1. In a stencil printing apparatus comprising a pair of parallel, oppositely grooved stencil guides, and means for reciprocating a stencil along said guides through a printing zone, whereby an indefinite number of prints may be obtained from one stencil so reciprocated, the combination, with said above described apparatus, ol a flexible sheet stencil having notches in either end and a carrier therefor comprising a rectangular frame of thin, still material having projections at either end adaptedv to engage said notches, said frame being adapted to slip into, and be reciprocated along, saidguides, and having a window therein of such extent as Ato expose the stencilized area of said flexible sheet.

2. A combination such as defined in claim 1 in which said flexible sheet stencil comprises a thin paper frame having substantially the same outlines as said carrier frame, and a sheet of loose f'lbred paper cemen d to said lpaper frame.

3. A combination such as den'ed in claim 1- in which said stiiT carrier frame comprises a base portion of thin sheet metal, and an upper portion having substantially the same exterior outlines, said base portion having projections at either end bent upwardly and inwardly to overlie the ends of said upper portion and also to engage the notches in the stencil ends.

4. In a stencil printing apparatus comprising, a pair of oppositely revolving platen sectors and a pair of parallel, oppositely grooved stencil guides, the combination, with said above described apparatus, of a rectangular flexible sheet stencil, and a rectangular carrier having substantially the same external dimensions as said stencil and composed of an upper kframe and a lower frame each made of thin, stiff materiali and means for releasably clamping said stencils between said frames, said carrier being adapted to be slipped into, and be reciprocated along the grooves in said guides and between said sectors, and having a window therein of such extent as to expose the stencillized area of said flexible sheet.

5. A combination such as defined in claim 4 in which said exible sheet stencil comprises a thin paper frame having substantially the same outline as said carrier, and a sheet of loose bred paper cemented to said paper frame.

6. In a stencil printing apparatus the combination of a stencil carrier comprising upper and lower rectangular frames of thin, stiff material and means for releasably clamping a thin, fiexible stencil sheet between them, the inner edges of the side portions of the upper frame projecting beyond those of the lower frame, a pair of rotating platen sectors the upper one of which has an ink carrying surface composed of yielding material the side edges of which overlap the inner side edges of said upper car- Iier frame, and means for guiding said carrier between said sectors at a level such that the portions of said upper sector surface over the opening in said upper rectangular frame will be forced downward between the edges of said opening; whereby a flexible stencil sheet clamped in said holder may ex slightly away from said upper frame during the ink-applying action of said upper sector, thereby avoiding any shearing action against the edge of the lower frame.

7. The combination with an apparatus such as defined in claim 6, of a. stencil sheet having thin edge portions clamped between the upper and lower frame of said carrier.

8. The combination with an apparatus such as defined in claim 6, of a stencil sheet having thin edge portions clamped between the upper and lower frame of said carrier, the side edge portions of said sheet being faced with flexible but tougher reenforcing strips of widths substantially 4 those of the side portions of thel upper frame overlying them.

9. In a stencil printing apparatus comprising a pair of revoluble platen sectorsand a pair of parallel oppositely grooved guides for conducting stencils between said sectors, the combination with said above described apparatus. of a carrier adapted to reciprocate in said grooves between said sectors and to carry a flexible stencil sheet releasably clamped therein, a iixed stop for one end of said carrier so located as to maintain the other end thereof within the bite of said revolving-sectors, a member slidingly mounted adjacent one of said guides, and yielding means normally forcing said member toward said stop, said carrier having a projection from one face thereof adapted to be positively engaged by said member when the latter is forced toward said stop.

10. In a stencil printing apparatus, the combination of a pair of parallel. oppositely grooved guide strips adjustable toward and from one an,- other to hold either wide or narrow stencils, two revoluble platen sectors, journaled one above and the other below the plane of said guides with the upper surface of the lower sector slightly below the plane of the lower surfaces of said guide strips, the upper sector having a face formed of elastic material, a portion of the surface of which carries ink, a relatively wide rectangular frame of thin sheetl metal adapted to slide along said grooved guides when the latter are spread apart sufficiently, the opening in which frame is narrower than are the faces of said platen sectors, whereby the sides thereof will be intermittently grasped between said platen sectors when the latter are revolving, means located wholly above or outside of the path of movement of said frame tending to pull it along said guides away from said platen sectors whenever it is released by said sectors, a stop preventing said frame being withdrawn so far from said sectors as to no longer be within their intermittent grasp, and a relatively large flexible stencil sheet yieldingly held in said. frame; whereby the printing' field of said stencil is deflected into a plane below the grooves in said guides in each printing operation by the pressure of the elastic face of said upper sector, and the adjustable guides may be moved toward one another over the relatively wide face of the lower platen sector whenever a narrower ink-bearing sector and stencils are to be used in the printing operation.

l1. In a stencil printing apparatus comprising a pair of oppositely rotating platen sectors, one of which carries ink and a pair of oppositely grooved parallel stencil guidesextending through the printing zone formed by said sectors, the combination, with said above described apparatus, of a stencil carrier adapted to slide along said guides comprising two thin rectangular frames superposed one upon the other and provided with means for releasably clamping a thin, flexible stencil sheet between them; the said platen sectors having a width sufficient to slightly o'verlap the inner edge portions of said carrier and so grip and move it. and anyl stencil carried thereby. through said printing zone.

12. An apparatus such as dened in claim 11 combined with automatic means for retracting said carrier along said guides after it has been released from the grip of said sectors.

13. An apparatus such as defined in claim 1l combined with a thin paper stencil clamped in said carrier.

HARMON P. ELLIOTT. 

